Final answer:
Applying Snell's law of refraction and given that the angle between refracted and reflected rays is 90°, the refractive index of glass when a ray of light strikes it at 60°, would be √3.
Step-by-step explanation:
The given question pertains to the physics concept of light refraction and the nature of light when it encounters a change in medium, like glass in this case. Given that the refracted and reflected rays are perpendicular to each other when the light strikes the glass plate at an angle of 60°, Snell's law of refraction can be used to calculate the refractive index of glass.
The law of refraction is expressed as n₁ sin θ₁ = n₂ sin θ₂, where n₁ and n₂ are the indices of refraction for the two media, and θ₁ and θ₂ are the incident and refracted angles respectively. Considering the fact that the refracted and reflected rays are perpendicular (totaling 90 degrees), if the incident angle is 60°, the refracted angle must be 30°. This leads us to the equation n₁ * sin(60) = n₂ * sin(30). In the context of this equation, n₁ is the refractive index of the air (which is 1), which allows us to solve for n₂, the refractive index of glass.
By solving the equation, the refractive index of glass in this case comes out to be √3 which matches option (d) in your question.
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